The embodiments herein generally relate to power controllers and more particularly to integrated power quality modules.
Power quality plays a significant role in modern electronics, including in industries such as aerospace, ground vehicles, and industrial systems. For example, the commercial aircraft business is moving toward having electrical no-bleed-air environmental control systems, electrical variable-frequency power distribution systems, and electrical actuation. Similarly, for example, ground vehicles have migrated toward hybrid electric technology, where the main propulsion is performed by electric drives. Therefore, a substantial demand for increased power electronics in these areas has emerged.
These trends have significantly increased the installed electrical sources and loads, along with the challenges to accommodate electrical equipment to new platforms. This has led to increased operating voltages and efforts to reduce system losses, weight, and volume. A new set of electrical power quality requirements has been created to satisfy system performance. Traditionally, the sources (electric generators) are required to maintain certain power quality requirements and their loads are to be able to operate at these requirements. Also, the loads are required to not create power quality disturbances on the distribution buses above certain levels. Yet the probability of power quality issues has increased due to the large number of installed electric equipment and their complex interactions. Further, power quality issues may lead to catastrophic failures and/or events that should be prevented.
Power quality is required to allow for compatibility between sources and loads installed on the same power distribution bus. For example, a typical aircraft electric power system consists of a main power source, an emergency power source, power conversion equipment, control/protection equipment, and an interconnect network (i.e. wires, cables and connectors). The main power source comprises the main generators, driven by the aircraft propulsion engines. Emergency power is extracted from aircraft batteries, aircraft independent auxiliary power units (APUs), and aircraft ram air or hydraulically driven generators.
Power quality requirements for AC electrical equipment consist of a large number of parameters. Some of these parameters include current distortion, inrush current, voltage distortion, voltage modulation, power factor, phase balance and DC content. Power quality is a major concern for aircraft because a large number of electric power systems and equipment are installed on the same electrical bus. The power quality of these systems and equipment has stringent requirements to ensure that all power supplies/utilization equipment function properly together.
For power supply equipment additional monitoring features are implemented to detect and isolate equipment, or groups of equipment, that may experience a power quality issue. This isolation capability is to protect other operating power supplies and utilization equipment. For power utilization equipment, strict power quality requirements are imposed. Some reasons for the requirements are as follows: (a) equipment contributing to power quality problems cause other equipment to fail; (b) equipment is prevented from achieving its design performance or reliability due to the reduced power quality of the source; (c) perhaps to meet a desired minimum weight, equipment designed with no power margin tends to be more susceptible to power quality issues; and (d) equipment designed to minimize weight tends to create power quality issues.
There are scenarios where a single equipment failure may propagate and create bus power quality non-compliance, leading to potential additional failures. For example, a single power source failure could fail to isolate power quality deficiencies and may damage utilization equipment or other power sources. A single utilization equipment failure may create non-compliant power quality bus and lead to other utilization equipment failure and/or power source failure. Utilization equipment can experience a destructive failure due to its own power quality non-compliance, and utilization equipment may fail regardless of the source of the power quality non-compliance on the bus.